D.C. Council member Michael A. Brown on Thursday made an opponent’s prior arrest for possessing marijuana an issue in the campaign, accusing challenger David Grosso of trying to conceal his nearly 20-year-old criminal record.

In a televised debate on NewsChannel 8’s “NewsTalk With Bruce DePuyt,” Brown (I-At Large) mentioned Grosso’s 1993 arrest for marijuana possession several times as both sparred over ethics and character, including Brown’s failure to pay his taxes, mortgage and rent on time.

The exchange underscores the increasingly tense campaign as Brown, Grosso, Mary Brooks Beatty (R), incumbent Vincent B. Orange (D) and three other candidates compete for two at-large council seats, one of which is reserved for a non-Democrat.

The Washington Post reported a week ago that Grosso, an independent, was arrested in May 1993 in Okaloosa County, Fla., on a misdemeanor marijuana charge.

Grosso, 22 at the time, said he pleaded guilty to possessing less than two grams of marijuana while on a camping trip and paid a fine. Grosso, a lawyer and former council staffer, described the arrest as a “turning point” in his life and says he has not used drugs since.

But in the debate, Brown turned to Grosso’s arrest to defend himself against charges from Beatty and Grosso that some of his past personal and financial decisions should disqualify him from serving on the council.

“What council member Brown has shown is he’s really not fit to be in office for a lot of reasons,” Grosso said early in the debate. “His inability to manage finances, whether it be his own taxes, his rent, his mortgage, all of these things.”

Before Grosso could finish his sentence, Brown cut him off and referenced Grosso’s 1993 arrest.

“Get your facts right,” said Brown, stating that recent news stories about his finances have been inaccurate. “If you are going to talk about my personal issues, talk about yours. Talk about your arrest and conviction. Talk about it.”

Grosso responded, “Well, I think everyone knows, 20 years ago.”

Again, Brown interrupted.

“Talk about it,” Brown demanded. “You talk about being transparent. Why didn’t you tell the voter upfront” about the arrest?

Grosso went on to explain the charge and said that he had admitted to it on his applications to college and law school.

Grosso, who appeared surprised by Brown’s forcefulness, then made a passing reference to Brown’s own record. In 1997, at 32, Brown pleaded guilty to a federal misdemeanor charge that he made $4,000 in illegal campaign contributions to Sen. Edward M. Kennedy (D-Mass.).

“We can talk about 1997,” Grosso said. He then added, “20 years’ history is one thing; I haven’t had another thing happen my entire life.”

“Hey, Mike, I pay my rent, I pay my mortgages, I make sure I pay all my taxes,” Grosso said.

Grosso’s comments represent the challengers’ efforts to keep Brown’s past financial and professional troubles, including five suspensions of his driver’s license in the past eight years, as issues in front of the voters.

“You can’t run from your character,” Beatty said in the debate. “There is a pattern, and some issues that reflect how you serve the public.”

Brown, the son of the late commerce secretary Ronald H. Brown, said the focus should remain on his legislative record, including his push to maintain social services, build more affordable housing and get local companies to hire more District residents.

“My public trust has never been called into question,” Brown said in the debate. “You go to housing advocates, job advocates, folks fighting for the most vulnerable residents, they say Michael Brown has done his job.”

But Brown’s campaign remained hampered by limited funds after his allegation that his former treasurer stole $113,950 from his campaign account. In September, Brown updated his campaign finance reports to account for the loss, which left him with only $18,000 in the bank as of Aug. 10. The former campaign treasurer has denied the allegation, saying Brown authorized payments as salary.

The latest campaign finance reports, filed Wednesday night, show that Brown continues to struggle to make up for the money the campaign lost and that he remains at a disadvantage to Grosso. Brown reported that he raised $30,646 over the past two months and has about $16,000 on hand, records show.

Beatty also has about $16,000 in the bank, but Grosso reported $67,000 in available cash. Orange, who as the Democratic nominee is heavily favored to retain his seat, reported about $12,000 in the bank.

But Orange and Brown have both run citywide campaigns and may need less campaign cash than their challengers because of their name recognition among voters.

Orange largely steered clear of the feuding by Grosso, Brown and Beatty, instead joining all the candidates in the debate over traffic cameras, council ethics rules and whether the council should approve city contracts.

Statehood Green Party candidate Ann C. Wilcox and independents A.J. Cooper and Leon Swain, none of whom are well-funded, did not participate in Thursday’s debate. They are scheduled to debate on the show next week.

Mike DeBonis contributed to this report.